Biodiversity

I.  Biodiversity: The variety of living things

  1. Three kinds
  2. Genetic Diversity is the measure of the variety of different versions of the same genes within a species
  3. Species Diversity is the measure of the variety of organisms within individual communities or ecosystems
  4. Ecological Diversity means the richness and complexity of a biological community, including the number of niches, trophic levels and ecological processes.
  5. The Linnaean System of Classification
  6. A system of grouping different organisms in which organisms that more closely related to each other are grouped together.
  7. The system is a hierarchy.
  8. At the top are relatively few, broad categories that include diverse organisms
  9. Ex: The Animal Kingdom
  10. At the bottom are a lot of very narrow categories, each category containing very few distinct species.
  11. Ex: Species
  12. The hierarchy from most general to most specific is
  13. Kingdom Phylum Class Order Family Genus Species
  14. Kingdom
  15. The highest, most general level of classification
  16. Five kingdoms are
  17. Plants
  18. Animals
  19. Fungi
  20. Monera (bacteria)
  21. Protista
  22. Phylum (pl. phyla)
  23. The highest level in the animal kingdom
  24. All members of a phylum share a common body plan, though they may live in very different habitats and have very different lifestyles.
  25. All evolved from a common ancestor.
  26. Approximately 34 animal phyla
  27. Class
  28. Within each phylum the members are further divided into classes on the basis of major variation in the fundamental body plan, usually in adaptation to a particular way of life.
  29. Ex: Phylum= Gas engines, Classes=car, boat, airplane
  30. Order
  31. More specific than classes
  32. Ex: Class= Automobile, Order = Passenger Car
  33. Family
  34. More specific than order
  35. Ex: Order=Passenger Car, Family = Station Wagon
  36. Genus (pl. genera)
  37. More specific than family
  38. Ex: Family = Station Wagon, Genus = Subaru Wagon
  39. Species (pl. species)
  40. The most specific
  41. Ex: Genus = Subaru Wagon, Species = 1993 Subaru Wagon
  42. Scientific names are always italicized and always include the genus and specific epithet
  43. Ex: Homo sapiens- humans, Orcins orca – Killer Whale
  44. Benefits of Biodiversity
  45. Food
  46. All of our food comes from other organisms
  47. As many as 80,000 edible wild plant species could be utilized by humans
  48. Ex: Indonesia has 250 edible fruits and only 43 are cultivated widely.
  49. Drugs and Medicine
  50. >50% of all prescriptions contain some natural products
  51. Pharmaceutical products derived from developing world plants, animals and microbes generate $75-150 Billion/year.
  52. Ecological Benefits
  53. Soil formation, waste disposal, air and water purification, nutrient cycling, solar energy absorption and food production all depend on biodiversity.
  54. Total value = $33 trillion, year
  55. Biodiversity helps biological communities withstand environmental stress better and recover more quickly.
  56. 95% of the potential pests and disease-carrying organisms in the world are controlled by natural predators and competitors
  57. Aesthetic and Cultural Benefits
  58. People like nature
  59. Americans spend $104 Billion/year on wildlife-related recreation, while only $81 billion/year on new cars.
  60. Threats to biodiversity
  61. Extinction: the elimination of a species
  62. Normal process and in undisturbed ecosystems, the rate of extinction appears to be about 1 species lost/decade
  63. However, during this century, we’re losing 10,000 species/year or 27/day.
  64. Extirpation- loss of a population for a given area, local extinction or ecological extinction
  65. Human-Caused Reductions in Biodiversity
  66. In the last 150 years, the extinction rate has increased to thousands/decade
  67. Between 1/3 to 2/3 of all species could be extinct by the middle of the 21st Century.
  68. Reasons
  69. Habitat Alteration: #1 Cause
  70. Humans preempt 40% of the net primary productivity of the biosphere either by direct consumption or through interference.
  71. Temperate broad-leafed forests are the most dominated.
  72. Wetlands and estuaries are hit particularly hard because they support huge biodiversity
  73. Fragmentation: the reduction of habitat into smaller and smaller, more scattered patchesReduces biodiversity because many species need larger territoriesSmall isolated groups are susceptible to catastrophic events.
  74. Invasive Species Introductions: aliens introduced into habitats where they are not native
  75. Biological pollution
  76. Because they lack predators, parasites and competition they can turn into superaggressive ‘weedy’ invaders.
  77. Pollution
  78. Directly or indirectly leads to the reduction of populations
  79. Overexploitation
  80. Hunting and Fishing: Overharvesting can lead directly to extinctions Ex: The passenger pigeon
  81. Commercial Products and Live Specimens: Smuggling of furs, hides, horns, live specimens and folk medicines amounts to million of dollars/year
  82. Protecting Biodiversity
  83. Hunting and fishing laws regulate the age and quantity of individuals that can be killed
  84. Endangered Species Act
  85. Endangered Species are those that are in imminent danger of extinction, while threatened species are those likely to become endangered in the foreseeable future.
  86. 1995 Supreme Court ruled that not only the species, but its habitat must also be protected.
  87. Recovery Plans
  88. A plan must be developed to revoke a species’ endangered status.
  89. Reintroductions
  90. An endangered species can be recovered through reintroduction